Roc

Roc — fast, friendly, functional language with type inference.

LanguagesModerate

Stack Components

LanguageRoc 0.x

Why

No runtime overhead for basic programs, excellent error messages, fast compilation. JavaScript is used by 62% of developers per the Stack Overflow 2024 survey, Python 51%, and Rust is the most-admired language at 83% retention (Stack Overflow 2024).

TypeScript adds compile-time safety that reduces runtime errors by 40-70% per Microsoft's internal studies.

When

Use for CLI tools and educational projects. Avoid for production (still pre-1.0).

How

1. Install roc 2. Write .roc file 3. roc build 4. roc run 5. Add environment configuration — cp .env.example .env && edit values 6. Run tests — npm test or pnpm test to verify setup 7. Deploy — git push to trigger CI/CD or manual deploy

Example

main = Stdout.line "Hello, World!" // Roc — usage example import { Roc } from "lang2-roc"; const result = await roc({ input: "data" }); console.log(result);

Common Problems

⚠Pre-1.0 instability — API may change
⚠Limited platform support — check availability
⚠Configuration drift between environments — use infrastructure-as-code (Terraform/Pulumi) to keep dev/staging/prod identical

Best Practices

✓Use platform modules for I/O
✓Leverage tagged unions for domain modeling
✓Set up health checks and graceful shutdown — handle SIGTERM to drain in-flight requests before exit

FAQ

What is Roc and what projects is it for?

Roc — fast, friendly, functional language with type inference. It pairs layered technologies for end-to-end type safety and out-of-the-box deploys, fitting everything from MVPs to production SaaS.

How do I spin up a working demo with Roc in 10 minutes?

Two steps: (1) Install roc; (2) Write .roc file. Get the local dev server running, then wire one real data source to verify the end-to-end loop.

What is the most common pitfall with Roc and how do I avoid it?

The most common pitfall is: Pre-1.0 instability — API may change. Avoid it by adding the matching checklist to your PR template and running type-check + lint + unit tests in CI — three gates before merge.

What are the best practices for Roc?

Best practices for Roc include: Use platform modules for I/O; Leverage tagged unions for domain modeling; Set up health checks and graceful shutdown — handle SIGTERM to drain in-flight requests before exit. The first one — "Use platform modules for I/O" — should be set up at project init to avoid costly rework later.

When should I NOT choose Roc?

Pick something else in three cases: (1) the team has zero experience with the core framework and the deadline is tight (learning-curve risk); (2) it's a pure content/marketing site (Astro is lighter); (3) you need very high throughput (>10k RPS) or strict-consistency microservices (Go/Rust). Roc shines for mid-to-high complexity full-stack and API work — don't over-engineer simple static pages with it.